Preparation Of Several Nanomaterials And Investagation Of Their Intracellular Trafficking Network And Drug Loading Properties

Cancer is one of the major diseases that threat human health seriously.The construction of nano-cancarier for controlled drug release and the exploration of their intracellular pathways is of great significance for improving the efficacy of chemical diagnostic drugs in vivo.In this thesis,several different types of drug carrier platforms were fabricated and their intracellular pathways in the cell were explored in detail.Animal experiments were also conducted using one of the drug carriers.It was found that the synergistic use of drug-loaded nanocarrier release platform and autophagosome inhibitors would greatly improve the therapeutic effect of tumor.The other part of the thesis explored the use of polariz light to differenciate cancer cells and red blood cells according to the light they scattered due to the difference of cell morphology,which provided a new idea and method for cancer identification,diagnosis and treatment.The specific research is as follows:Multifunctional silicon-based nanoparticles were successfully prepared by electrochemical etching.We investigated and the influence of electrochemical etching conditions on their physical characteristics such as thickness and pore size.The drug loading activity was studied: the drug loading efficiency was highly depend on the sequence of the drug applied,ie.,the drug loading rate of the first load was higher,and that of the second load was lower.This character can ben used to control the drug ratio in a single drug carrier.Porous silicon nanoparticles enter the cell through Arf-6 independent endocytosis and are then transferred into the early endosome followed by transfered to the late endosome.They can be delivered through the cell by recycling the endosome and secret into the extracellular environment through GLUT4 process and melanosome vesicle pathway by MCF-7 cells.Anodic alumina nanotubes and PHBHHx nanoparticles were successfully prepared by means of modified pulse anodization process using galvanostatic mode and a solvent displacement method,respectively.The intracellularp athways of the two nanostructures in MCF-7 cells and He La cells were investigated.The anodic alumina nanotubes entered the cells through the caveolin-dependent endocytosis and Rab34-mediated micropinocytosis,while the PHBHHx nanoparticles entered the cell through the clathrin–dependent and caveolin-dependent pathway Rab34-mediated micropinocytosis endocytosis pathway.Both of them entered the cell through the classical endocytosis pathway: early endosome-late endosome – lysosome and can also be transferred to the early endosome by the liposome endocytosis process and then be transferred into the late endosome,finally into the lysosome to degrade in the cell.Two new intracellular pathways were identified(anodic alumina nanotubes: micropinocytosis-late endosome-lysosome;PHBHHx nanoparticles: micropinocytosis-early endosome-lysosome)in cells.Cells can transport them through the slow cycle endocytosis pathway and the apical cycle endocytosis pathway.The cells use slow endocytosis recycling pathway and GLUT4 exocytosis vesicles transport the two type of nanoparticles out of the cells.They can induce intracellular autophagy,and autophagy inhibitors can block their autophagy process.Animal experiments showed that the combined action of drug-loaded PHBHHx nanoparticles and chloroquine could significantly improve the therapeutic effect of tumor.In order to develop the best drug delivery vector,we should treat intracellular pathways as a single obstacle to effective drug delivery and evaluate them comprehensively.The drug release platform can be constructed by autophagy inhibitors and drug-loaded anodic aluminum nanotubes to improve the efficacy.In addition,we investigated the use of polarized light scattering method to identify cancer cells and red blood cells according to the difference of the light they scattered due to their difference in morphology for the first time.It was demonstrated this method is convenient and effective,paved a way for practicals application for the identification,diagnosis and treatment of cancer.